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My piece de resistance: (drumroll please...)

From what I understand, the current isolated storm cells have developed on a convergence wave tied into the circulation of the depression in Biscay. This "wave" will rotate and traverse slowly WNW through this evening to stall somewhere like this around midnight approx, against a cold front approaching from the west. The western extent being a line roughly from Birmingham - Bath - Weymouth. The cold front approaching from the west later tonight/early hours tomorrow will then push the storms back east again again, at the same time, providing greater destabilization of the atmosphere and greater forcing, thus fuelling many more storms to develop, possibly merging into clusters. So, to conclude, I would say the next few hours, any action will be focused in the below circled area; Then as we approach midnight, and the cold front provides greater forcing, the area in focus would be; This would be the area where storms would explode into life and become much more prominent. Then into day break tomorrow morning, the cold front edges east slowly to focus storms somewhere like this at breakfast time; And continually moving east to finish the day around here; A lively 18hrs or so coming up with storms becoming much more widespread into the night across Central, Eastern & South Eastern England.

I havent been that active on here but the shots I've got just amazing I dont think I've seen anything like this with the sun poruing down and so much happening above my location, west london here ready to also record my first time lapse. making use of my nikon l340 not a single drop of rain just lots of thunder and some great skies above.

Tuesday night. Winter Hill transmitter in background and Peel monument becomes visible. Those horses must have crapped themselves! https://mobile.twitter.com/EUStormMap/status/775953444452438016/video/1

Incredible storm cloud mushrooming before my eyes from that Nw London cell.

Thunder overhead, still no visible lightning!

A couple of vid caps from Tuesdays storms around Birmingham.....with luck we will see some overnight storms this evening, which will give us some easier photographic opportunitys

Sheeeeeeeez she's pretty

and what exactly is driving that storm down the M4? a 95 year old stuck in first gear??.......forget the met office, the AA and rac will be putting out warning for a very slow abnormal load on the m4 soon!

going for a poo then heading out with the cameras. It's a nice night and i only have to be up early tomorrow to buy Korn + Limp Bizkit tickets (for shame) so might just sit out in the field near my house (can see the west london/reading cell) and wait for dark.

Up she goes!

This is it boys and girls, from now on it's going to be one hell of a ride, enjoy the storms and stay safe, I'm off out with the camera, I hope to return with some nice shots.

Storm & Convective Forecast Issued 2016-09-15 21:21:06 Valid: 16/09/2016 00z to 17/09/2016 00z CONVECTIVE / STORM FORECAST - FRI 16TH-SEPT-2016 Synopsis Slack upper and surface flow pattern across the UK on Thursday, between upper trough to the west and upper low over France will be replaced by a more progressive / strengthening W/NWly flow at all levels on Friday, behind upper trough and attendant surface cold front moving in from the west. So unusually warm and humid plume that’s been across much of England and Wales since the beginning of the week will be kicked out and replaced by cooler and fresher conditions from the west. During this transition, thunderstorms are likely to become increasingly widespread across S and E England during Thursday night and Friday morning, before clearing east later on Friday. … S and E ENGLAND, MIDLANDS … Convergence north of W-E frontal boundary pushing up across the English Channel and a subtle shortwave moving NE appears to be the forcing mechanism for back-building lines of storms across Dorset, Hampshire and Sussex this evening. These storms are forecast by models to expand in coverage across central S and SE England (including London) and perhaps S/E Midlands overnight, as forcing and cooling increases aloft from the west. These storms will continue the tendency to back-build over some spots – leading to an enhanced risk of flash-flooding from rainfall rates as high as 30-40mm per/hr. Frequent cloud-to-ground lightning will pose an additional hazard. Also these storms will be capable of producing hail and gusty winds. There is a SLIGHT risk for central S and SE England during the first half of Friday morning for of flash-flooding. Eventually these storms and heavy showers will merge into a broad band of heavy thundery rain, with isolated embedded storms, that will spread east across much of S and E England … as the cold front moves in from the west. Lightning may become less prolific and more isolated during the morning as CAPE is reduced by cool outflow/cold pooling from overnight storms and also cooler and drier air undercutting from the west. But there will continue to be an isolated risk of flash-flooding from stronger convective cells, as well as a risk of gusty winds. Band of thundery rain with embedded storms eventually clearing east coast Friday evening. There is a MARGINAL risk over S and E England for the continued risk of flash-flooding, though there is a SLIGHT risk over the far SE of England –where a higher risk for stronger storms with flash-flooding will exist into the afternoon. Issued by: Nick Finnis http://www.netweather.tv/index.cgi?action=convective;sess=

I got a screen grab of that

re. storms following motorways......actually I did think there is some merit in this at one time........years ago (2006) I posted a thread on this very subject as indeed I'd felt looking at radar archives that there did seem to be a correlation between surface based thunderstorms and areas of artificial heating, certainly the urban heat effect is a well documented phenomena.........I did however, check the british motorway infrastructure and compared it to local topography and found that most UK motorways occupy natural valleys (easier to build I guess, less stuff to dig/blow up) and local topography can and does affect surface based storm motion, thus I concluded that it was just a coincidence back on current discussion, where's my damned storm! ....lol

If the Reading cell stays on its current trajectory, it may hit me by next Thursday. In all seriousness, as Chris said above, I'm a little too far west for this one. Roll on the famous winter blizzard of 2017!

Can just make out the anvil of the storm over west London from where I am at work at Gatwick Airport in Sussex.

I've not seen a warning like this!! http://www.metoffice.gov.uk/public/weather/warnings/#?tab=warnings&regionName=ee&fcTime=1473980400 An area of torrential, thundery rain is expected to develop across the region during early Friday morning bringing the potential for exceptionally large amounts of rain within a few hours. Frequent lightning and hail may be additional hazards. Whilst there remains some uncertainty about developments and areas affected, there could be major disruption. Please be prepared for the potential for very severe weather conditions bringing flash flooding and disruption to transport. A cold front approaching moist, unstable air is expected to generate a line of exceptionally heavy, thundery rain. Possible sustained hourly rates of more than 30 mm could result in totals of more than 100 mm in 3-4 hours. Particularly in urban areas, this could lead to flooding of properties and businesses and major disruption to transport.

Doom-mongerers (I accuse no one) can fox-trot right out of it. No model I've seen has noted any outbreaks of heavy rain/thunderstorms until around midnight and beyond (apart from the cells already witnessed this evening). We have seen it so so so many times where people gamble their houses on no action too early only for the atmosphere to erupt. There is of course no guarantee that it will - but we are at least 3 hours before anything ought to be expected to start kicking off anyway. Just thought I'd slip it in now in case anyone is planning on having a premature whinge

Oh leave William alone, he was harmless. I saw ACCAS mentioned on thew weather today and thought of him

There are some Alto Cumulus castellanus grimslius visible to my south...A good omen for later tonight, I feel...

Definite convection over Heathrow, very warm at 28C...

mb018538 above is along the right lines with the idea of a NW-SE split. The anomaly charts below suggest this to me, no complete agreement on placement and intensity of either the upper ridge or trough. http://www.cpc.noaa.gov/products/predictions/610day/500mb.php http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

This evening's Met Off Fax Chart issued at 19.00 shows the set-up this evening. Cold Front still out West but moving towards us; trough line giving tonight's storms; and the warm (cold) front creeping up across the Channel from the Continent. This little lot effectively merge over our Region overnight and into tomorrow morning to give some localised very heavy rain and widespread lightning for our Region by the end of the night. It could be an interesting 18 hours of weather! Fax Chart for 18.00 Thurs Met Off forecast this evening for Fri 05.00

Yep. Boris bikes are no good in 4" of water.

Don't forget your MW radios peeps, there's a lot of strikes not shown on lightning detectors online, your average MW radio will detect local strikes up to 20 miles away. Just tune to a weak station and listen!! After a while you can also tell the difference between CG and IC strikes, CG's sound like a sudden crack and IC's crackle!!!

Just a couple of pics of the Tuesdays storm that i forgot about this pic as the storm was aproaching and this one as it left to the north,this was the inflow that kept on feeding the storm and produced numerous lightning as it collided into the storm

Was it Piers Corbyn???

And for those who haven't got any storms yet. Please take a look at the orange moon it's stunning

Followed by fresh, fresh, fresh

By far the most uncomfortable evening of the year, so close and muggy. Hurry up cold front!

A promising UKMO for T144 - signs of another stalling trough - though not a lot of support elsewhere in the models tonight ECM not showing exactly the same idea but with the main trough far to the west, always the chance of a late summer southerly again

I thought Newtown Popplewell was destroyed by a raging castellanus blitz linked to hurricane hooray Henry. ....

Tomorrow is looking so much better,really looking forward to seeing the backend of this awful humid weather go,so tired of it,can't wait for the Autumn freshness to roll in,not a minute to soon. No idea how anybody could wish this to hang around,sorry.

I would say that it was because there was very little shear yesterday, so once the cap was initially broken you had that explosive development, but soon as the downdrafts became established they just swamped the updrafts. This cuts off the supply of warm air killing the cell and possibly cooling the air in the general area, inhibiting convection from Breaking the cap again. By the time this cooler air had dissipated, the sun had set and convection was waning anyway. That's what I feel Might have happened from a purely amateur perspective. :-)

A lovely Autumnal morning here.

Models and forecasts all differ slightly again but maybe some agreement over the SW Midlands, CS England and West Country this evening. If I were chasing (which I may still do) I would be targeting Oxfordshire/Wiltshire/Gloucestershire on current forecasts.

I'm going to try to get some shut eye. Could be a night of little sleep if goes to plan so will try and get some in now. Good luck all, stay safe and I hope none of us have to suffer any flooding!

Oh crap.....that be me then

Would be wonderful to see a line of lightning strikes to form between Belgium and the south of the uk. I can picture it. Asking for too much?

I can see the thundery clouds approaching from the east ... bye bye long hot summer, you will be missed

We have mamatus! Are they severe?

I have a cracking view of the cell that's working it's way toward Reading. Hearing lots of distant deep rumbles of the thunder. Feels like the whole anvil is almost on top of us.

This is that there Blandford cell...

Very good view from here on that cell I'm almost under it but not quite can hear the thunder it's almost stationary View from the deck chair..

The GIF above from a French weather site shows nicely how the warm humid plume across southern Britain is squeezed out both from the south and west as cold fronts approach from both directions, quite an unsual evolution, but the pincer movement of fronts into a rather unstable airmass later should hopefully create some lively storms over next 24-36hrs before the cooler and fresher Atlantic air wins out from the west:

ECM and UKMO showing azores high ridging northwest to produce mid atlantic heights forcing low pressure to attack from the NW as we move through next week, resulting in a much cooler trend. GFS toying around with this scenario. Until then, one more day of summery conditions, then a cool down for all, generally unsettled in the north, drier and still very pleasant in the south with high teen/low 20 maxima- which is very respectable for mid September. The atlantic isn't much of a power horse at the moment, traditionally it cranks into about third gear when we hit the autumn equinox, but its interesting to note how meridional the flow has been recently, and how ex hurricane features have simply fizzled.. I think it may be due to the anamolous warm SST's over the north atlantic, resulting in a weaker temp gradient and consequently less fuel to ignite the jetstream, all suggestive we could see much more in the way of anticyclonic conditions this winter season, with low pressure becoming sluggish and taking about turns, with greater continental and arctic influences.. we shall see.